Natural Lands - the magazine of Natural Lands spring-summer 2020 issue - Page 8

6 one out of four. gone. Scientists don’t use the word “staggering” lightly, but the numbers warrant it: since 1970, nearly three billion birds have disappeared from the US and Canada. A team of scientists from seven research institutions released the first-ever comprehensive assessment of net population changes in North America last fall. All told, the bird population is down by 2.9 billion breeding adults across all habitats—even among birds considered very common like sparrows, blackbirds, warblers, finches, and swallows. “Habitat loss is likely to be a driving factor in these declines,” say the authors, “particularly agricultural intensification and development.” The problem of declining habitat is exacerbated as birds are forced to adjust their range in response to climate change. The Eastern Meadowlark is one bird species facing staggering losses in numbers. Birds are the best-studied group of wildlife, according to Adam Smith, a coauthor of the study and biostatistician for Environment and Climate Change Canada. “With this study, we have finally managed to come up with a way to estimate the number of birds in North America, to get to a point where we trust the math. And it turns out, over less than a single human lifetime, we’ve lost almost a third of our birds.” For scientists, this documented mass decline and predicted extinctions are resounding warning bells. “It is reasonable to expect that whatever trends are observed in bird populations will be mirrored by other animals throughout that ecosystem, including mammals, amphibians, reptiles, and even fish,” said Mike Coll, manager of Natural Lands’ Hildacy Preserve and adjunct professor at Temple University. “The study tells us that not only are bird populations being decimated by human activities, land use choices, and a changing climate, but that also entire systems of living things no longer have the habitat and conditions they need to survive.” “ Birds are an ecological litmus paper. They warn us of things out of balance, “ sending out signals wherever there is deterioration in the ecosystem. — Roger Tory Peterson, noted ornithologist and naturalist Bill Moses (all) How can you help? shrink your lawn. Lawns are barren wastelands for wildlife. Consider replacing sections of lawn with a meadow, or with a bed of native plants. Layering a variety of native species— ground covers, shrubs, understory, and overstory—offers diversity of food sources and shelter for birds. avoid or reduce the use of pesticides. One billion pounds of pesticides are applied each year in the U.S., which can cause direct harm to birds and reduce the number of insects available to them. become a citizen scientist. To understand how birds are faring, scientists need hundreds of thousands of people to report what they’re seeing in backyards, neighborhoods, and wild places around the world. Natural Lands offers birding events throughout the year to get you started. (Visit to check out upcoming happenings.) plant a tree.